During the operation phase of an electronic system, a clean and continual power supply is a sine qua non for maintaining a normal performance. However, the contemporary public electric power supply system is likely to be degenerated by the breakdown and short circuit occurred to the power lines. Therefore, uninterruptible power supply (UPS) has been widely introduced in the client side applications to fix the problems of the abnormalities encountered by the input power side.
FIG. 1 illustrates an elevation view of a conventional standalone uninterruptible power supply according to the prior art. As shown in FIG. 1, a conventional standalone uninterruptible power supply 10 is made up of a display panel 11, a housing 12, a power supply module 13, and a battery module 14, wherein the display panel 11 is mounted on the housing 12 for displaying the system status information of the uninterruptible power supply 10. The housing 12 is configured to receive the power supply module 13 and the battery module 14. The power supply module 13 is the core of the uninterruptible power supply 10, and is made up of a plurality of power conversion elements, including rectifiers, chargers, controllers, inverters, converters, switch devices, and so on. Besides, the power supply module 13 and the battery module 14 are fixedly mounted inside the housing 12.
FIG. 2 illustrates a circuit block diagram of the uninterruptible power supply 10 shown in FIG. 1. In FIG. 2, the solid arrowheaded lines interconnecting circuit blocks represent power lines and the dashed arrowheaded lines interconnecting circuit blocks represent signal lines. As depicted in FIG. 2, the uninterruptible power supply 10 is connected to an external power source 21 and a load 22, and is made up of a display panel 11, a housing 12, a power supply module 13, a battery module 14, and a switch device 15. The display panel 11 is mounted on the housing 12 for displaying the system status information of the uninterruptible power supply 10. The power supply module 13 includes a microcontroller 131 connected to the display panel 11 for providing the system status information of the uninterruptible power supply 10 for display on the display panel 11. The battery module 14 is connected to the power supply module 13 for storing electric power. The switch device 15 is connected between the external power source 21 and the load 22. When the power supply module 13 or the battery module 14 is to be extracted for maintenance, the switch device 15 can be turned on manually so that the external power source 21 can supply electric power to the load 22 through a bypass route (not shown).
Under normal conditions, the uninterruptible power supply 10 enables the power supply module 13 to perform rectification, filtration, and conversion to the input AC power received from the external power source 21 and supply the converted electric power to the load 22. Meanwhile, the power supply module 13 is configured to charge the battery module 14 and supply electric power to the display panel 11. The microcontroller 131 of the power supply module 13 can provide the system status information of the uninterruptible power supply 10 to the display panel 11 for display. During the operation phase of the power supply module 13, the power supply module 13 can store electric power in the battery module 14. When the external power source 21 is malfunctioned or becomes abnormal, the internal switch device of the power supply module 13 (not shown) performs a switching operation to enable the battery module 14 to supply electric power. Under this condition, the power supply module 13 can convert the electric power outputted from battery module 14 and output the converted electric power to the load 22. Meanwhile, the electric power required for powering the display panel 11 is supplied from the power supply module 13, and thereby the display panel 11 can continue displaying the system status information of the uninterruptible power supply 10.
The conventional standalone uninterruptible power supply 10 requires a manual switching operation to shunt the switch device 15 to a bypass route. Hence, when the power supply module 13 is malfunctioned or needs to be repaired, the uninterruptible power supply 10 can not automatically manipulate the switch device 15 to allow the external power source 21 to supply electric power to the load 22 through a bypass route. As a result, the application field of the conventional standalone uninterruptible power supply will be restricted. Besides, the display panel 11 is powered by the power supply module 13 and driven by the microcontroller 131 for displaying the system status information of the uninterruptible power supply 10. When the power supply module 13 is malfunctioned or extracted from the uninterruptible power supply 10 for repair, the power supply module 13 can not power the display panel 11. Under this condition, the display elements of the display panel, for example, LED devices or LCD devices, can not operate for information display, and thus the user is not possible to obtain the operation data and important system information of the uninterruptible power supply, including input voltage, output voltage, battery status, and working temperature.
There is a need to develop an uninterruptible power supply that can continuously display its system status information when its internal power supply module is inoperable or extracted from the housing of the uninterruptible power supply.